From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756424AbdLVSiF (ORCPT ); Fri, 22 Dec 2017 13:38:05 -0500 Received: from mail.kernel.org ([198.145.29.99]:47712 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752549AbdLVSiE (ORCPT ); Fri, 22 Dec 2017 13:38:04 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7B6AD218DA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=rostedt@goodmis.org Date: Fri, 22 Dec 2017 13:38:01 -0500 From: Steven Rostedt To: Josh Poimboeuf Cc: LKML , Ingo Molnar , Thomas Gleixner , Andrew Morton , x86@kernel.org, Linus Torvalds Subject: Re: [RFC][PATCH][REGRESSION FIX] x86/ftrace: Add ORC annotation to 64 bit ftrace assembly Message-ID: <20171222133801.3c9b1078@gandalf.local.home> In-Reply-To: <20171222183024.47yadfkznhwhrlgf@treble> References: <20171222131841.4564c975@gandalf.local.home> <20171222183024.47yadfkznhwhrlgf@treble> X-Mailer: Claws Mail 3.14.0 (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 22 Dec 2017 12:30:24 -0600 Josh Poimboeuf wrote: > I'm officially on vacation but I got a chance to look at this myself a > few minutes ago. This looks mostly right. In theory, you should able > to mark those as functions by changing END to ENDPROC. Then you won't > need all the UNWIND_HINT_FUNCs. Yep, that was my first solution, but as you found, objtool complained about it. > > I tried making that change, but objtool thinks the stack frame is still > modified when the functions return. I didn't see anything obvious in > save_mcount_regs or restore_mcount_regs that should cause it to think > that. I'll need to look into it a little more. Thanks! Worse comes to worse, we can keep this change, and you can enjoy your holidays. I just need this fixed before 4.15 is released. I'll be jumping into objtool shortly, to see if I can merge the code from recordmcount.c with it too. I'm going to need to learn ORC and DWARF to start on extending the function tracer to act more like tracepoints (like I discussed with Linus in Prague). -- Steve